multi-downloader-nx_mirror/modules/cdm.ts

import { KeyContainer, Session } from "./license";
import fs from "fs";
import { console } from "./log";
import got from "got";
import { workingDir } from "./module.cfg-loader";
import path from "path";
import { ReadError, Response } from "got";
import { Device } from "./playready/device";
import Cdm from "./playready/cdm";
import { PSSH } from "./playready/pssh";

//read cdm files located in the same directory
let privateKey: Buffer = Buffer.from([]),
    identifierBlob: Buffer = Buffer.from([]),
    prd: Buffer = Buffer.from([]),
    prd_cdm: Cdm | undefined;
export let cdm: "widevine" | "playready";
export let canDecrypt: boolean;
try {
    const files_prd = fs.readdirSync(path.join(workingDir, "playready"));
    const prd_file_found = files_prd.find(f => f.includes('.prd'))
    if (prd_file_found) {
        const file_prd = path.join(workingDir, "playready", prd_file_found);
        const stats = fs.statSync(file_prd);
        if (stats.size < 1024 * 8 && stats.isFile()) {
            const fileContents = fs.readFileSync(file_prd, {
                encoding: "utf8",
            });
            if (fileContents.includes("CERT")) {
                prd = fs.readFileSync(file_prd);
                const device = Device.loads(prd);
                prd_cdm = Cdm.fromDevice(device);
            }
        }
    }

    const files_wvd = fs.readdirSync(path.join(workingDir, "widevine"));
    files_wvd.forEach(function (file) {
        file = path.join(workingDir, "widevine", file);
        const stats = fs.statSync(file);
        if (stats.size < 1024 * 8 && stats.isFile()) {
            const fileContents = fs.readFileSync(file, { encoding: "utf8" });
            if (
                fileContents.includes("-BEGIN PRIVATE KEY-") ||
                fileContents.includes("-BEGIN RSA PRIVATE KEY-")
            ) {
                privateKey = fs.readFileSync(file);
            }
            if (fileContents.includes("widevine_cdm_version")) {
                identifierBlob = fs.readFileSync(file);
            }
        }
    });

    if (privateKey.length !== 0 && identifierBlob.length !== 0) {
        cdm = "widevine";
        canDecrypt = true;
    } else if (prd.length !== 0) {
        cdm = "playready";
        canDecrypt = true;
    } else if (privateKey.length == 0) {
        console.warn("Private key missing");
        canDecrypt = false;
    } else if (identifierBlob.length == 0) {
        console.warn("Identifier blob missing");
        canDecrypt = false;
    } else if (prd.length == 0) {
        console.warn("PRD is missing");
        canDecrypt = false;
    }
} catch (e) {
    console.error(e);
    canDecrypt = false;
}

export async function getKeysWVD(
    pssh: string | undefined,
    licenseServer: string,
    authData: Record<string, string>
): Promise<KeyContainer[]> {
    if (!pssh || !canDecrypt) return [];
    //pssh found in the mpd manifest
    const psshBuffer = Buffer.from(pssh, "base64");

    //Create a new widevine session
    const session = new Session({ privateKey, identifierBlob }, psshBuffer);

    //Generate license
    let response;
    try {
        response = await got(licenseServer, {
            method: "POST",
            body: session.createLicenseRequest(),
            headers: authData,
            responseType: "text",
        });
    } catch (_error) {
        const error = _error as {
            name: string;
        } & ReadError & {
                res: Response<unknown>;
            };
        if (
            error.response &&
            error.response.statusCode &&
            error.response.statusMessage
        ) {
            console.error(
                `${error.name} ${error.response.statusCode}: ${error.response.statusMessage}`
            );
        } else {
            console.error(`${error.name}: ${error.code || error.message}`);
        }
        if (error.response && !error.res) {
            error.res = error.response;
            const docTitle = (error.res.body as string).match(
                /<title>(.*)<\/title>/
            );
            if (error.res.body && docTitle) {
                console.error(docTitle[1]);
            }
        }
        if (
            error.res &&
            error.res.body &&
            error.response.statusCode &&
            error.response.statusCode != 404 &&
            error.response.statusCode != 403
        ) {
            console.error("Body:", error.res.body);
        }
        return [];
    }

    if (response.statusCode === 200) {
        //Parse License and return keys
        try {
            const json = JSON.parse(response.body);
            return session.parseLicense(Buffer.from(json["license"], "base64"));
        } catch {
            return session.parseLicense(response.rawBody);
        }
    } else {
        console.info(
            "License request failed:",
            response.statusMessage,
            response.body
        );
        return [];
    }
}

export async function getKeysPRD(
    pssh: string | undefined,
    licenseServer: string,
    authData: Record<string, string>
): Promise<KeyContainer[] | undefined> {
    if (!pssh || !canDecrypt || !prd_cdm) return [];
    const pssh_parsed = new PSSH(pssh);

    //Create a new playready session
    const session = prd_cdm.getLicenseChallenge(
        pssh_parsed.get_wrm_headers(true)[0]
    );

    //Generate license
    let response;
    try {
        response = await got(licenseServer, {
            method: "POST",
            body: session,
            headers: authData,
            responseType: "text",
        });
    } catch (_error) {
        const error = _error as {
            name: string;
        } & ReadError & {
                res: Response<unknown>;
            };
        if (
            error.response &&
            error.response.statusCode &&
            error.response.statusMessage
        ) {
            console.error(
                `${error.name} ${error.response.statusCode}: ${error.response.statusMessage}`
            );
        } else {
            console.error(`${error.name}: ${error.code || error.message}`);
        }
        if (error.response && !error.res) {
            error.res = error.response;
            const docTitle = (error.res.body as string).match(
                /<title>(.*)<\/title>/
            );
            if (error.res.body && docTitle) {
                console.error(docTitle[1]);
            }
        }
        if (
            error.res &&
            error.res.body &&
            error.response.statusCode &&
            error.response.statusCode != 404 &&
            error.response.statusCode != 403
        ) {
            console.error("Body:", error.res.body);
        }
        return [];
    }

    if (response.statusCode === 200) {
        //Parse License and return keys
        try {
            const keys = prd_cdm.parseLicense(response.body);

            return keys.map((k) => {
                return {
                    kid: k.key_id,
                    key: k.key,
                };
            });
        } catch {
            return undefined;
        }
    } else {
        console.info(
            "License request failed:",
            response.statusMessage,
            response.body
        );
        return [];
    }
}